So I received my first Einstein and Cybersync Commander today, and I'm trying to trigger a 580ex ii as a slave. However, I'm reading that the 580ex ii can't be triggered as an optical slave by a non-Canon flash. So my question(s) are: 1) Is this true? And 2) If so, how can I trigger the 580ex ii as a slave? Can I use the cord from the Einstein to the 580ex ii or do I pretty much have to pony up for another PCB wireless trigger?
Thanks in advance for the help!